A single-source MCP server build at AppMatic Tech runs 4 weeks from discovery to handover. Multi-source builds with multiple data system integrations run 6 to 8 weeks. Enterprise builds with per-user authentication, custom audit logging, and compliance requirements run 8 to 12 weeks.
These timelines hold across AppMatic Tech's MCP server builds because the scope is defined precisely before implementation begins. Timeline overruns on MCP projects almost always trace back to one of three sources: undocumented APIs that require reverse-engineering during integration, compliance requirements that surface after architecture is decided, or authentication complexity that was underestimated during scoping.
This article breaks down what happens in each week of a standard 4-week single-source build and explains the factors that expand the timeline for more complex engagements.
Week 1: Discovery and Architecture
Week 1 is the highest-leverage week of the build. The decisions made here constrain every subsequent week.
AppMatic Tech's discovery process covers: what data sources the MCP server needs to connect to, what query patterns the LLM needs to support against those sources, what authentication mechanism the data source requires, what compliance obligations apply to the data being exposed, and what concurrent request volume the server needs to handle at production scale.
From these inputs AppMatic Tech produces a resource specification: a written definition of each MCP resource the server will expose, including the resource name, description, schema, filter parameters, and supported operations. The resource specification is reviewed and approved before implementation begins.
Week 1 also covers the infrastructure decisions: transport mechanism, deployment target, connection pool sizing, and caching strategy. These decisions are documented in a technical design document that accompanies the resource specification.
The discovery week is not billable waiting time. It produces deliverables that directly accelerate implementation. A build that skips formal discovery and moves directly to implementation typically recovers the discovery cost in the form of implementation rework when the resource schema does not match the LLM's query patterns.
Week 2: Implementation
Week 2 is the primary implementation week. By the end of Week 2, the MCP server should be functionally complete against the resource specification.
AppMatic Tech's implementation sequence starts with the protocol handler and resource definitions, which can be tested independently before the data access layer is connected. This means the LLM routing behaviour and schema validation are verified against mock data before any real database queries run, which makes isolating issues faster when they appear.
The data access layer is connected and integrated against the staging data source in the second half of Week 2. By the end of the week, the server should be handling real queries against real data in the staging environment.
Week 2 is where timeline extensions first appear if the data source has undocumented behaviour. A CRM API that returns different field structures for different record types, an ERP that requires a VPN connection that was not mentioned during discovery, or a database schema that differs from the documentation all add time to the data access layer implementation. AppMatic Tech documents these discoveries and updates the timeline estimate when they occur rather than absorbing them silently until the delivery date slips.
Week 3: Integration and LLM Validation
Week 3 connects the completed MCP server to the actual LLM client and validates query routing behaviour under realistic user scenarios.
The LLM validation session in Week 3 is the check that unit tests cannot replace. AppMatic Tech runs the LLM through 20 to 30 realistic user queries and observes which resources the LLM routes each query to, what parameters it sends, and whether the responses it receives produce correct natural language outputs. Routing errors that appear in this session are fixed by refining resource descriptions, not by changing the data access layer.
Week 3 also covers load testing. AppMatic Tech runs the server at the expected production peak concurrent request volume and measures P95 response time, connection pool behaviour, and error rate. Load test failures are addressed before the build moves to Week 4.
Week 4: QA, Documentation, and Handover
Week 4 covers the deployment checklist, documentation, and client handover.
The deployment checklist AppMatic Tech runs before every production launch covers 12 checks across authentication, schema validation, load behaviour, audit logging, and LLM query routing. The checklist takes two to three hours to complete and is delivered to the client as a signed-off document.
Documentation covers the resource schema reference, the deployment and configuration guide, the secrets management setup, and the audit log format and access instructions. AppMatic Tech delivers documentation as part of the codebase handover, not as a separate deliverable that follows the launch.
Handover includes a live walkthrough session with the client's engineering team covering the codebase structure, the resource definitions, the deployment configuration, and the secret rotation procedure.
What Extends the Timeline
Undocumented APIs. A data source with incomplete or inaccurate API documentation adds 1 to 2 weeks to the integration phase. AppMatic Tech requests API documentation and sandbox access at the start of Week 1 and flags documentation gaps as soon as they are discovered.
Multi-source integrations. Each additional data source adds approximately 2 to 3 weeks to the base timeline, depending on the source's API quality and authentication complexity. A build connecting a CRM, an ERP, and an internal database runs 8 to 10 weeks rather than 4.
Per-user authentication. Designing and implementing per-user token passthrough for multi-tenant deployments adds 2 weeks to a build that would otherwise use simple API key authentication.
Compliance requirements. HIPAA audit logging, SOC 2 evidence generation, and GDPR data residency requirements each add specific engineering work. AppMatic Tech scopes compliance requirements in Week 1 and includes them in the fixed-scope proposal. Compliance requirements that surface after the proposal is agreed require a change order.
Timeline Reference
| Build Type | Timeline | Cost Range |
|---|---|---|
| Single-source, API key auth | 4 weeks | $25K |
| Single-source, OAuth / token passthrough | 5 to 6 weeks | $30K–$40K |
| Multi-source (2 to 3 sources) | 6 to 8 weeks | $35K–$55K |
| Enterprise (4+ sources, compliance, audit logging) | 8 to 12 weeks | $50K–$75K |
For full cost detail by build type, see How Much Does MCP Server Development Cost in 2026. For the deployment validation checks that close out every build, see MCP Server Deployment Checklist.
For a delivered example, see how AppMatic Tech built the ConstructionMCP platform. Full engagement details are on the MCP Server Development service page. Contact AppMatic Tech at contact@appmatictech.com to scope a build.